Behaviors of Eutectic Crystals below Their Eutectic Points

The present investigation is concerned with an anomalous eutectic reaction which takes place at a temperature lower than their ordinary eutectic points, provided that the eutectic system contains at least an intermetallic compound as one of the components. These experiments were carried out for the system of iron and silicon. It was found out that there are two kinds of diffusion rates of silicon into iron, which suggests that a liquid with concentration near to the composition of the compound FeSi is able to coexist with primary solid solutions of iron and silicon at a temperature lower than the ordinary eutectic points.